Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flows from Operating Activities
Net income	$ 63,621	$ 50,473
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization, and accretion, including amortization of purchase accounting adjustments and market value adjustments	(309)	1,646
Provision for loan and lease losses	7,986	6,154
Share-based compensation cost - equity awards	4,734	3,721
Loss/(gain) on sale of OREO and long-lived assets, net of impairment	670	(746)
Loss/(gain) on sale of available for sale securities	59	0
Expense/(benefit) for deferred income taxes	10,992	(10,565)
Originations of mortgage loans held for sale	(336,400)	(393,924)
Proceeds from sales of mortgage loans held for sale	367,487	440,337
Realized and unrealized (gain)/loss on mortgage loans held for sale, net	(9,320)	(13,689)
Other operating activities, net	(13,113)	(20,933)
Net Cash Provided by Operating Activities	96,407	62,474
Cash Flows from Investing Activities
Proceeds from maturities, prepayments and calls of available for sale securities	149,987	113,940
Purchases of available for sale securities, net of available for sale securities acquired	(194,543)	(491,055)
Proceeds from maturities, prepayments and calls of held to maturity securities	2,288	2,968
Purchases of equity securities, net of equity securities acquired	(2,452)	(200)
Proceeds from sales of equity securities	61,038	0
Increase in loans, net of loans acquired	(145,201)	(60,609)
Proceeds from sales of premises and equipment	1,408	7
Purchases of premises and equipment, net of premises and equipment acquired	(5,798)	(2,761)
Proceeds from dispositions of OREO	5,318	4,374
Cash paid for additional investment in tax credit entities	(750)	(795)
Payments to Acquire Businesses, Net of Cash Acquired	99,312	0
Other investing activities, net	(745)	6,327
Net Cash Used in Investing Activities	(30,138)	(427,804)
Cash Flows from Financing Activities
Increase/(decrease) in deposits, net of deposits acquired	440,470	(95,916)
Net change in short-term borrowings	(90,802)	(60,440)
Proceeds from long-term debt, net of long-term debt acquired	200,227	0
Repayments of long-term debt	(651,684)	(622)
Cash dividends paid on common stock	(19,933)	(16,126)
Cash dividends paid on preferred stock	(3,598)	(3,599)
Net share-based compensation stock transactions	(2,581)	(4,169)
Net proceeds from issuance of common stock	0	485,194
Net Cash Used in Financing Activities	(127,901)	304,322
Net Increase (Decrease) In Cash and Cash Equivalents	(61,632)	(61,008)
Cash and Cash Equivalents at Beginning of Period	625,724	1,362,126
Cash and Cash Equivalents at End of Period	564,092	1,301,118
Supplemental Schedule of Non-cash Activities
Acquisition of real estate in settlement of loans	1,757	2,733
Common stock issued in acquisitions	214,659	0
Cash paid for:
Interest on deposits and borrowings	37,035	19,850
Income taxes, net	$ 101	$ 39,609